The NSA is one of the world's most notoriously secretive and powerful government agencies, guarding its powerful hacking tools and massive caches of collected data under layers of security clearances and world-class technical protections. But it turns out that three times in three years, that expensive security has been undone by one of its own contract employees simply carrying those secrets out the door.
In 2013, an NSA contractor named Edward Snowden walked out of the agency's building in Oahu, Hawaii, carrying a USB drive full of thousands of top-secret documents. Last year, a 53-year-old Booz Allen contractor for the NSA named Hal Martin was arrested last year for taking 50 terabytes out of the agency over a period as long two decades. And Thursday, the Wall Street Journal reported that in 2015, a third contract employee of the NSA in as many years took home a trove of classified materials that included both software code and other information that the agency uses in its offensive hacking operations, as well as details of how it protects US systems from hacker adversaries.

That classified data, which wasn't authorized to be removed from the perimeter of the facility where that contractor worked, was then stolen from the contractor's home computer by Russian spies, who exploited the unnamed employee's installation of antivirus software from Kaspersky, a Russian company.